19. Chemical Thermodynamics

The normal boiling point of Br21l2 is 58.8 °C, and its molar enthalpy of vaporization is ΔHvap = 29.6 kJ>mol. (b) Calculate the value of ΔS when 1.00 mol of Br21l2 is vaporized at 58.8 °C.

The element gallium (Ga) freezes at 29.8 °C, and its molar enthalpy of fusion is ΔHfus = 5.59 kJ>mol. (b) Calculate the value of ΔS when 60.0 g of Ga(l) solidifies at 29.8 °C.

Calculate the change in entropy that occurs in the system when 1.00 mole of diethyl ether (C4H10O) condenses from a gas to a liquid at its normal boiling point (34.6 °C). See Table 11.7 for heats of vaporization.

Naphthalene, better known as 'mothballs,' has bp = 218 °C and ΔHvap = 43.3 k# J>mol. What is the entropy of vaporiza tion, ΔSvap in J>1K mol2 for naphthalene?

For the vaporization of benzene, ∆Hvap = 30.7 kJ/mol and ∆Svap = 87.0 J/(K*mol). Does benzene boil at 70 °C and 1 atm pressure? Calculate the normal boiling point of benzene.

For the vaporization of benzene, ∆Hvap = 30.7 kJ/mol and ∆Svap = 87.0 J/(K*mol). Calculate ∆Ssurr and ∆Stotal at: (a) 70 °C

For the melting point of sodium chloride, ΔHfusion = 28.16 kJ/mol and ΔSfusion = 26.22 J/(K·mol). Does NaCl melt at 1100 K? Calculate the melting point of NaCl.

Chloroform has ΔHvaporization = 29.2 kJ>mol and boils at 61.2 °C. What is the value of ΔSvaporization for chloroform?

Calculate the change in entropy that occurs in the system when 1.00 mole of isopropyl alcohol (C3H8O) melts at its melting point (-89.5 °C). See Table 11.9 for heats of fusion.